Andre Przywara | ffbacb0 | 2019-07-10 17:27:17 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved. |
| 3 | * |
| 4 | * SPDX-License-Identifier: BSD-3-Clause |
| 5 | */ |
| 6 | |
| 7 | /* |
| 8 | * Contains generic routines to fix up the device tree blob passed on to |
| 9 | * payloads like BL32 and BL33 (and further down the boot chain). |
| 10 | * This allows to easily add PSCI nodes, when the original DT does not have |
| 11 | * it or advertises another method. |
Andre Przywara | 83fc839 | 2019-07-15 09:00:23 +0100 | [diff] [blame] | 12 | * Also it supports to add reserved memory nodes to describe memory that |
| 13 | * is used by the secure world, so that non-secure software avoids using |
| 14 | * that. |
Andre Przywara | ffbacb0 | 2019-07-10 17:27:17 +0100 | [diff] [blame] | 15 | */ |
| 16 | |
| 17 | #include <string.h> |
| 18 | |
| 19 | #include <libfdt.h> |
| 20 | |
| 21 | #include <common/debug.h> |
| 22 | #include <drivers/console.h> |
| 23 | #include <lib/psci/psci.h> |
| 24 | |
| 25 | #include <common/fdt_fixup.h> |
| 26 | |
| 27 | static int append_psci_compatible(void *fdt, int offs, const char *str) |
| 28 | { |
| 29 | return fdt_appendprop(fdt, offs, "compatible", str, strlen(str) + 1); |
| 30 | } |
| 31 | |
| 32 | int dt_add_psci_node(void *fdt) |
| 33 | { |
| 34 | int offs; |
| 35 | |
| 36 | if (fdt_path_offset(fdt, "/psci") >= 0) { |
| 37 | WARN("PSCI Device Tree node already exists!\n"); |
| 38 | return 0; |
| 39 | } |
| 40 | |
| 41 | offs = fdt_path_offset(fdt, "/"); |
| 42 | if (offs < 0) |
| 43 | return -1; |
| 44 | offs = fdt_add_subnode(fdt, offs, "psci"); |
| 45 | if (offs < 0) |
| 46 | return -1; |
| 47 | if (append_psci_compatible(fdt, offs, "arm,psci-1.0")) |
| 48 | return -1; |
| 49 | if (append_psci_compatible(fdt, offs, "arm,psci-0.2")) |
| 50 | return -1; |
| 51 | if (append_psci_compatible(fdt, offs, "arm,psci")) |
| 52 | return -1; |
| 53 | if (fdt_setprop_string(fdt, offs, "method", "smc")) |
| 54 | return -1; |
| 55 | if (fdt_setprop_u32(fdt, offs, "cpu_suspend", PSCI_CPU_SUSPEND_AARCH64)) |
| 56 | return -1; |
| 57 | if (fdt_setprop_u32(fdt, offs, "cpu_off", PSCI_CPU_OFF)) |
| 58 | return -1; |
| 59 | if (fdt_setprop_u32(fdt, offs, "cpu_on", PSCI_CPU_ON_AARCH64)) |
| 60 | return -1; |
| 61 | if (fdt_setprop_u32(fdt, offs, "sys_poweroff", PSCI_SYSTEM_OFF)) |
| 62 | return -1; |
| 63 | if (fdt_setprop_u32(fdt, offs, "sys_reset", PSCI_SYSTEM_RESET)) |
| 64 | return -1; |
| 65 | return 0; |
| 66 | } |
| 67 | |
| 68 | /* |
| 69 | * Find the first subnode that has a "device_type" property with the value |
| 70 | * "cpu" and which's enable-method is not "psci" (yet). |
| 71 | * Returns 0 if no such subnode is found, so all have already been patched |
| 72 | * or none have to be patched in the first place. |
| 73 | * Returns 1 if *one* such subnode has been found and successfully changed |
| 74 | * to "psci". |
| 75 | * Returns -1 on error. |
| 76 | * |
| 77 | * Call in a loop until it returns 0. Recalculate the node offset after |
| 78 | * it has returned 1. |
| 79 | */ |
| 80 | static int dt_update_one_cpu_node(void *fdt, int offset) |
| 81 | { |
| 82 | int offs; |
| 83 | |
| 84 | /* Iterate over all subnodes to find those with device_type = "cpu". */ |
| 85 | for (offs = fdt_first_subnode(fdt, offset); offs >= 0; |
| 86 | offs = fdt_next_subnode(fdt, offs)) { |
| 87 | const char *prop; |
| 88 | int len; |
| 89 | |
| 90 | prop = fdt_getprop(fdt, offs, "device_type", &len); |
| 91 | if (!prop) |
| 92 | continue; |
| 93 | if (memcmp(prop, "cpu", 4) != 0 || len != 4) |
| 94 | continue; |
| 95 | |
| 96 | /* Ignore any nodes which already use "psci". */ |
| 97 | prop = fdt_getprop(fdt, offs, "enable-method", &len); |
| 98 | if (prop && memcmp(prop, "psci", 5) == 0 && len == 5) |
| 99 | continue; |
| 100 | |
| 101 | if (fdt_setprop_string(fdt, offs, "enable-method", "psci")) |
| 102 | return -1; |
| 103 | /* |
| 104 | * Subnode found and patched. |
| 105 | * Restart to accommodate potentially changed offsets. |
| 106 | */ |
| 107 | return 1; |
| 108 | } |
| 109 | |
| 110 | if (offs == -FDT_ERR_NOTFOUND) |
| 111 | return 0; |
| 112 | |
| 113 | return offs; |
| 114 | } |
| 115 | |
| 116 | int dt_add_psci_cpu_enable_methods(void *fdt) |
| 117 | { |
| 118 | int offs, ret; |
| 119 | |
| 120 | do { |
| 121 | offs = fdt_path_offset(fdt, "/cpus"); |
| 122 | if (offs < 0) |
| 123 | return offs; |
| 124 | |
| 125 | ret = dt_update_one_cpu_node(fdt, offs); |
| 126 | } while (ret > 0); |
| 127 | |
| 128 | return ret; |
| 129 | } |
Andre Przywara | 83fc839 | 2019-07-15 09:00:23 +0100 | [diff] [blame] | 130 | |
| 131 | #define HIGH_BITS(x) ((sizeof(x) > 4) ? ((x) >> 32) : (typeof(x))0) |
| 132 | |
| 133 | int fdt_add_reserved_memory(void *dtb, const char *node_name, |
| 134 | uintptr_t base, size_t size) |
| 135 | { |
| 136 | int offs = fdt_path_offset(dtb, "/reserved-memory"); |
| 137 | uint32_t addresses[3]; |
| 138 | |
| 139 | if (offs < 0) { /* create if not existing yet */ |
| 140 | offs = fdt_add_subnode(dtb, 0, "reserved-memory"); |
| 141 | if (offs < 0) |
| 142 | return offs; |
| 143 | fdt_setprop_u32(dtb, offs, "#address-cells", 2); |
| 144 | fdt_setprop_u32(dtb, offs, "#size-cells", 1); |
| 145 | fdt_setprop(dtb, offs, "ranges", NULL, 0); |
| 146 | } |
| 147 | |
| 148 | addresses[0] = cpu_to_fdt32(HIGH_BITS(base)); |
| 149 | addresses[1] = cpu_to_fdt32(base & 0xffffffff); |
| 150 | addresses[2] = cpu_to_fdt32(size & 0xffffffff); |
| 151 | offs = fdt_add_subnode(dtb, offs, node_name); |
| 152 | fdt_setprop(dtb, offs, "no-map", NULL, 0); |
| 153 | fdt_setprop(dtb, offs, "reg", addresses, 12); |
| 154 | |
| 155 | return 0; |
| 156 | } |